This invention relates to a recreational apparatus with a trough-shaped runway and at least one four wheel car with a self-steering front axle.
Recreational apparatuses of the aforementioned kind are generally known under the term "summer bobsled run" and are frequently built in the mountains for better use of a slope. As an example of the state of the art reference is made to DE-OS 29 17 074, which shows a four wheel car with self-steering front axle for such a recreational apparatus with a trough-shaped runway. In the known cars the front wheels are mounted on a rigid axle beam, which in turn can swing around an axle bolt, which is sloped in the center of the car from the top to the front bottom. In this manner the front axle steers automatically to the right, when its left front wheel is lifted owing to the arch of the runway, and automatically to the left, when its right front wheel, is lifted owing to the arch of the runway. In this manner the car automatically has the tendency to steer to the lowest region of the chute-like runway, and an equilibrium between the centrifugal force moving the car to the outside and the steering tendency to the lower region of the runway is obtained in the curves. Furthermore, the oscillating axle design enables the driver to tilt into the curve with the car in order to maintain equilibrium.
The drawback with the known recreational apparatuses is that they can be used only in the mountains on account of the necessity of a slope. For flat land there are no comparable recreational apparatuses. There are, of course, so-called go-cart apparatuses, where motorized vehicles drive on a usually flat runway. The vehicles are designed with an understanding of motor vehicles and have a front axle that is steered by means of a steering wheel. Therefore, go-cart vehicles do not produce the feeling of a sled ride on a bobsled run.